What is a quarry tile?
A quarry tile is a floor tile of fired clay. Its defining features are its substantial thickness, its unglazed surface and the warm, uneven colour that comes from the clay body and the firing — from yellow and ochre through red-brown to almost black.
Despite the name it has nothing to do with a stone quarry; the word derives from the French carré, square. Traditionally these tiles were hand-formed and fired in simple kilns, which produced dimensional variation and colour differences between batches. Modern machine-pressed versions are more accurate in size but lose some of that liveliness. Closely related names are terracotta tile and, in the Netherlands, plavuis.
Properties
- Thickness. Much greater than an ordinary ceramic tile: roughly 10 to 25 mm depending on type and format. Check the build-up height in advance, especially at doors and thresholds.
- Absorbent. Unglazed quarry tiles take up water, grease and dirt. Left untreated, they will stain permanently.
- Mass. Thickness and density together make them a good heat store — pleasant in combination with underfloor heating and passive solar gain.
- Hard wearing. With good maintenance they last for decades; wear produces patina rather than damage.
Laying and treating
Lay quarry tiles in a full mortar or adhesive bed with no voids: a thick tile over a hollow spot will crack under a point load. Because of the size tolerances of hand-formed tiles, always work with a generous joint — 5 to 10 mm is normal — and mix tiles from several boxes to avoid colour banding.
The critical step is the aftercare. Seal the tiles before grouting, or the grout will soak into the porous face and leave a grey haze that is next to impossible to remove. After grouting comes the final finish: an oil or wax treatment gives a matt, warm appearance but needs periodic maintenance; a synthetic impregnation is lower maintenance but changes the look more.
Laying quarry tiles: checks before and during the job
- Check the build-up height: Especially at doors and thresholds, because quarry tiles are much thicker than ordinary ceramic tiles.
- Full mortar or adhesive bed, no voids: A thick tile over a hollow spot will crack under a point load.
- Work with a generous joint: Allows for the size tolerances of hand-formed tiles.
- Mix tiles from several boxes: Avoids colour banding.
- Seal before grouting: Otherwise the grout soaks into the porous face and leaves a grey haze that is next to impossible to remove.
Note with underfloor heating: quarry tiles conduct heat well, but their thickness slows the control response. Follow the screed’s commissioning heating cycle and bring the floor up to temperature in stages before tiling.
Related terms
- Screed
- Poured floor
- Tile adhesive
- Terracotta floor tile
- Patina
Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.